Automatic repeating firearm having a magazine transfer port and closure means therefor



Nov. 24, 1970 N LAGOS 3,541,715

AUTOMATIC REPEATING FIREARM HAVING A MAGAZINE TRANSFER PORT AND CLOSURE MEANS THEREFOR Filed July 1, 1968 5 Sheets-Sheet 1 LOO3 FIG. I

FIG. 3'

INVENTZOR NICOLAOS LAGOS ATTZMRWEY BYI Nov. 24, 1970 N. LAGOS AUTOMATIC REPEATING TRANSFER PORT AND FIREARM HAVING A MAGAZIN CLOSURE MEANS THEREFOR 3 Sheets-Sheet 2 Filed July 1, 1968 INVENTOR NICOLAOS LAGOS BY. ATTO NR mm 3 mm mm. my

ww mm o: N: mv we 3 on g H5 mm United States Patent Ofice Patented Nov. 24, 1970 US. CI. 4217 Claims ABSTRACT OF THE DISCLOSURE A magazine for unused cartridges parallels the barrel of a firearm and has a lateral transfer port through which unused cartridges are sequentially transferred into a cartridge-receiving chamber formed as a rearward extension of the barrel and including a cartridge ejection port. A breech block slidably disposed in the cartridge-receiving chamber is driven rearwardly on detonation of a cartridge within the rearward end of the barrel to open the cartridge ejection port. On rearward movement of a detonated cartridge with the breech block, the former strikes an internal abutment and is twisted outwardly through the ejection port. After the initial part of its rearward movement, the breech block engages a transfer port closure to move the latter rearwardly to open such transfer port. Further rearward movement of the breech block actuates a transfer lever to move a cartridge from the magazine through the transfer port and into the cartridge-receiving chamber from which it is pushed forwardly into the rearward end of the barrel by the breech block.

The present invention relates to new and useful firearms and more particularly to shotguns of the automatic or self-loading type.

Although automatic firearms are already well known, many of the existing constructions, particularly in the case of shotguns, are relatively slow in their operation or have highly intricate and consequently very expensive mechanisms.

It is accordingly a principal object of the present invention to provide a self-loading firearm and particularly a self-loading shotgun which is highly effective in its operation.

It is a further object of the invention to provide a firearm with a relatively uncomplicated mechanism thereby reducing the likelihood of faults occurring in the mechanism.

It is yet another object of the present invention to provide a firearm, the manufacture of which can be carried out in a simple and effective manner.

Yet another object of the present invention is to provide a firearm having a relatively fast automatic re-load operation.

In accordance with the present invention, these and other objects are achieved by the provision of a firearm comprising a stock, a barrel opening at its breech into a cartridge-receiving chamber having a cartridge ejection port, a magazine tube substantially parallel to said barrel, a transfer port interconnecting said barrel and said receiving chamber for the transfer therethrough of a car tridge out of said magazine tube into said receiving chamber, spring means adapted to urge cartridges disposed within said magazine tube axially therealong towards said transfer port, a transfer port closure member slidably mounted for movement between a closed position covering said transfer port and an open position exposing said transfer port, a breech block adapted for sliding movement between a closed position covering said ejection port and an open position exposing said ejection port, transfer lever means adapted to urge a cartridge out of said magazine tube through said transfer port into said receiving chamber when said transfer port closure member is in its open position, trigger operated means adapted to detonate a cartridge within said barrel, means which will be described hereinafter in greater detail and which are adapted to move said transfer port closure member and said breech block from said closed positions in a particular sequence to said open positions on the detonation of a cartridge within said barrel, and spring means adapted to return said transfer port closure member and said breech block from said open positions to said closed positions.

The invention will now be described merely by way of illustration with reference to the accompanying drawings in which:

FIG. 1 is a perspective view, partly in section, of one embodiment of a firearm in accordance with the invention,

FIG. 2 is a transverse section along the line 22 of FIG. 1,

FIG. 3 is a transverse section along the line 3-3 of FIG. 2,

FIG. 4 is a perspective view of a suitable trigger mechanism in its released position for the firearm of FIG. 1,

FIG. 5 is a longitudinal vertical section through the trigger mechanism of FIG. 4 with the mechanism in its cocked position,

FIG. 6 is a horizontal section through the firearm along the line 6-6 of FIG. 1, showing the relative positions of the various structural components at the instant that a cartridge is being detonated,

FIG. 7 is a vertical section along the line 77 of FIG. 6 additionally showing a portion of the stock of the firearm,

FIG. 8 is a transverse vertical section along the line 88 of FIG. 6,

FIG. 9 is a similar horizontal section to that shown in FIG. 6 being taken along the line 9-9 of FIG. 1, except that the various structural components are shown in their relative positions at an instant subsequent to the detonation of a cartridge and during the transfer of a cartridge from the magazine tube to the receiving chamber,

FIG. 10 is a longitudinal vertical section along the line 10-10 of FIG. 9 additionally showing a portion of the stock of the firearm, and

FIG. 11 is a transverse vertical section along the line 11-11 of FIG. 9.

Like numerals of reference indicate like parts in the various figures.

The firearm illustrated in the drawings comprises a stock 12, a barrel 14 and a magazine tube 16. Referring to FIG. 6, it will be seen that the barrel 14 and the magazine tube 16 are substantially parallel to each other.

Referring now to FIG. 6, it will be seen that the magazine tube 16 is provided with a feed port 18 through which cartridges 20, 22 may be inserted by hand. Such cartridges are urged axially rearwardly, for a reason which will become apparent as the description proceeds, by means of a pusher plate 30 mounted on a helical compression spring 32 disposed forwardly of the cartridge 22 in the magazine tube 16. To prevent egress of the cartridges 20, 22 out through the feed port 18, a spring pawl 34 is provided suitably in the lower inner surface of the magazine tube 16. To permit transfer of a cartridge from the magazine tube 16 to the barrel 14 as will be explained in greater detail hereinafter, the spring pawl 34 is so disposed that the cartridge 20 abutting thereagainst is transversely aligned with a transfer port 36 provided in a wall 38 between the barrel 14 and the magazine tube 16.

At this juncture, it should perhaps be explained that the edges of the feed port 18 may be usefully bevelled so I as to facilitate insertion of cartridges.

Referring now to both FIGS. 6' and 7, it will be seen that the cartridge 24 disposed at the rear end of the bar rel 14 is prevented from further movement by its abutment with shoulders at the breech. The cartridge 24 is maintained in position by a breech block 42 urged forwardly by a helical compression spring 44 through a shaft 46 received in a depression 48 provided in the rearward end of the breech block 42, disc 50 being provided at the rear end of the shaft 46 to engage the spring 44. The rear end of the spring 44 is supported in a manner which will hereinafter be explained.

A cartridge-ejector port 52 is provided in a cartridge receiving chamber 54 (FIG. 9) provided rearwardly of the barrel 14. For reasons which will become apparent as the description proceeds, forward and rearward edges 56 and 58 respectively of the ejection port 52 are bevelled to facilitate the ejection of a cartridge 24 as shown in FIG. 9.

Referring again to FIGS. 6 and 7, it will be seen that, with the structural components in the positions illustrated the ejector port 52 is closed or covered by breech block 42. It will also be noted that the transfer port 36 is covered by a transfer port closure member 60, hereinafter referred to as door 60, this door being mounted for sliding axial movement from the forward closed position shown in FIG. 6 to the open position shown in FIG. 9. To this end, the door is guided by dividing walls 62 and 64 between the magazine tube 16 and a bore forming a rearward extension of the cartridge receiving chamber 54. The door is additionally provided with a transverse arm 66 slidingly received on shaft 46.

The transfer lever means provided for urging a cartridge out of the magazine tube 16 through the transfer port 36 into the receiving chamber 54 will best be understood by reference to FIGS. 7, 8, 10 and 11, from which it will be seen that the breech block 42 is provided in its undersurface with a recess 68 adapted to receive a lug 70 rigidly secured to a transfer control rod 72. This lug 70 is also provided with a cam surface 74 which is used to cock a hammer 76 of a trigger mechanism as will shortly be explained.

The transfer control rod 72 is also provided with a relatively short horizontal cam projection 78 which engages the lower end of a lever 80 centrally pivoted at 82 and terminating at its other end in an arcuate cartridgeengaging finger 84 disposed within the magazine tube 16 adjacent the transfer port 36. The lever 80 is normally retained in the position shown in FIG. 8 by a small compression spring 86, the ends of which are received in seatings 88 and 90.

Referring now to FIG. 7, it will be noted that in a preferred construction according to the invention, the transfer control rod 72 extends. rearwardly to engage a helical compression spring 92 disposed within a chamber 94 provided in the stock 12.

Reference will now briefly be made to the trigger mechanism illustrated in FIGS. 4 and 5. It will be seen that the trigger mechanism is mounted on a support member 96 and comprises a trigger 100 disposed within a trigger guard 98. The trigger mechanism may be mounted on the firearm in any convenient manner. The trigger 100 is pivoted at 104 and is used to actuate the hammer 76 which is mounted on a semicircular carrier 118 pivoted at 108. The linkage between the trigger 100 and the hammer 76 comprises the pawl disc 112 and the link arm 110. The pawl disc 112 is provided with a pawl tooth 120 which engages the upper end of the trigger 100. The hammer 76 is urged upwardly to the position shown in FIG. 4 by a spring 114 but is normally maintained in the position shown in FIG. 5 by the pawl disc 112 until the trigger 100 is pulled rearwardly.

Before describing the operation of the firearm, reference will be made to the preferred method of securing the stock 12 to the remainder of the firearm. For this purpose, interconnecting member 124 having a male thread 126 is engaged with a corresponding female thread 128 provided in the stock 12. The member 124 is provided with three forwardly directed projections 130, 132 and 134 (FIG. 2). As will be seen from FIG. 6, the generally cylindrical projection 130 is received within the rearward end of the magazine tube 16. The generally cylindrical projection 132 is received in the rear end of the bore 55 and serves as a seat for the compression spring 44. The projection 134 which has a generally rectangular cross section is received within an opening 136 provided for this purpose and has a substantially central cylindrical opening 138 therethrough for the sliding passage of the transfer control rod 72 to the compression spring 92 housed in the stock 12.

The functioning of the firearm shown in the drawings will be explained by first referring to FIGS. 6, 7 and 8 in which the various structural components are shown in the positions which they will have at the instant that the trigger 100 is pulled to release the hammer 76 causing the latter to strike a firing pin 140 slidingly mounted in the breech block 42 and normally urged to its rearward position by compression spring 142. Forward movement of the firing pin 140 against the base detonator of cartridge 24 causes the shot to be driven forwardly along the barrel 14 and, under the explosive influence of the detonation, the breech block 42 is driven rearwardly through the receiving chamber 54 against the effects of springs 44 and 92. Prior to this rearward movement of the breech block 42, the hammer 76, the lever 80 and the door 60 are in the positions shown in FIGS. 6, 7 and 8.

As the breech block 42 moves in the rearward direc tion, the transfer control rod 72 also moves rearwardly and the cam surface 74 of the lug'70 engages the hammer 76 and returns the latter to the cocked position shown in FIG. 5 in which it is then held by the trigger mechanism as will be readily appreciated by those skilled in the art. On further rearward movement of the breech block 42, the rear surface of the breech block 42 engages the transverse arm 66 of the door 60 and this also commences to move rearwardly.

Rearward movement of the breech block 42 will continue and eventually its forward end will be level with the rearward extremity of the ejector port 52. Up to this time, the discharged cartridge 24 will have moved rearwardly with the breech block 42 but, at this instant, the inner edge of the rear surface of the cartridge 24 strikes an abutment 144 provided for the purpose of twisting the cartridge to the position shown in FIG. 9 causing this cartridge to be ejected through the ejection port 52.

Further rearward movement of the breech block 42 and the door 60 takes place until the latter has cleared the transfer port 36. At about this time, the cam 78 engages the lower end of the lever 80 and causes the latter to rotate about its pivot 82 from the position shown in FIG. 8 to that shown in FIG. 11. This movement causes cartridge 20 to be transferred from the magazinue tube 16 to the receiving chamber 54 through the transfer port 36. The remaining cartridge or cartridges in the magazine tube will now move rearwardly under the urging of compressison spring 32 until the rearward end of the first cartridge 22 in FIG. 6, engages the radially inwardly projecting upper end 84 of lever 80.

At this stage, all the energy from the detonation has been absorbed by the compression springs 44 and 92 and these springs now serve to reverse the direction of movement of the breech block 42 to drive the latter for wardly towards its position shown in FIGS. 6 and 7. During this forward movement of the breech block 42, the disc 50 engages the rear surface of the transverse arm original position as shown in FIG. 6.

As the forward movement of the breech block 42 and the door 60 continues, the latter commences to close the transfer port 36. The cam projection 78 then moves forwardly out of engagement with the lower end of lever 80 and permits the upper end 84 of this lever to be retracted under the influence of spring 86 back into the wall of the magazine tube 16 so in turn allowing the cartridge 22 to move into the position occupied by the cartridge 20 in FIG. 6.

Since the trigger mechanism was cocked during the previously described rearward movement of the breech block 42, the firearm is now ready for a further firing operation.

It will be appreciated that numerous modifications may be made to the structure hereinbefore specifically described without departing from the spirit and scope of the invention. It will be appreciated, for example, that various grooves for guiding the several moving parts of the firearm may be provided. Detailed description of such features is, however, considered to be superfluous since such features would be obvious to persons skilled in the art.

What I claim is:

1. A firearm comprising a stock, a barrel adapted to accommodate a cartridge within its rearwardrnost end and opening at its breech into a cartridge-receiving chamber having a cartridge ejection port, a magazine tube substantially parallel to said barrel, a transfer port interconnecting said magazine tube and said cartridge-receiving chamber and oifset axially and rearwardly with respect to said cartridge ejection port for the transfer through said transfer port of a cartridge out of said magazine tube into said cartridge-receiving chamber, spring means adapted to urge cartridges disposed within said magazine tube axially therealong towards said transfer port and into transverse alignment with said transfer port, abutment means within said magazine tube for abutment with a cartridge therein for preventin said spring means urging such a cartridge axially out of transverse alignment with said transfer port, a breech block slidingly disposed within said cartridge-receiving chamber for axial movement on detonation of a cartridge within said barrel between a forwardmost position in which said breech block closessaid cartridge ejection port and a rearwardrnost position in which said breech block is disposed rearwardly of said transfer port for the transfer therethrough of a cartridge out of said magazine tube and into said cartridge-receiving chamber, a transfer port closure member adapted for sliding movement between a closed position covering said transfer port and an open position exposing said transfer port, a sliding interconnection between said breech block and said transfer port closure member whereby rearward axial movement of said breech block from said forwardmost position thereof initially occurs without movement of said transfer port closure member until said cartridge ejection port is partially opened after which said breech block and said transfer port closure member undergo conjoint rearward axial movement to expose said transfer port and whereby said breech block and said transfer port closure member undergo conjoint forward axial movement from their rearwardmost positions to close said cartridge ejection port and said transfer port respectively, transfer lever means operatively associated with said breech block and adapted to urge a cartridge out of said magazine tube through said transfer port into said cartridge-receiving chamber when said transfer port closure member is disposed in its open position on axial movement of said breech block, trigger operated means adapted to detonate a cartridge within said barrel, cartridge-ejector means adapted to engage a detonated cartridge on rearward movement of such a cartridge out of said barrel and into said cartridge-receiving chamber and to eject such a cartridge thrOugh said cartridge ejection port, and spring means adapted to return said transfer port closure member from said open position into said closed position and to move said breech block into said forwardmost position thereof in turn to push a cartridge from said cartridgereceiving chamber into said rearwardmost end of said barrel for subsequent detonation therein.

2. A firearm as claimed in claim 1 in which said magazine tube is provided with a feed port through which cartridges may be inserted thereinto and in which said abutment means comprises a pawl means adapted to prevent egress of cartridges from said magazine tube through said feed port but to permit insertion of cartridges thereinto.

3. A firearm as claimed in claim 1 in which said stock is detachably secured to the remainder of said firearm by means of a threaded inter-connecting member adapted to engage a corresponding thread in said stock.

4. A firearm as claimed in claim l in which said spring means adapted to return said transfer port closure member into said closed position and to move said breech block into said forwardmost position thereof comprises a helical compression spring adapted to be compressed during rearward axial movement of said breech block.

5. A firearm as claimed in claim 4 in which said breech block and said helical compression spring are linked by a shaft passing through a transverse arm secured to said transfer port closure member for limited axial sliding movement of said transverse arm along said shaft during initial rearward axial movement of said breech block from said forwardmost position thereof.

6. A firearm as claimed in claim 5 in which said breech block is connected to a transfer control rod adapted to actuate said transfer lever means on rearward axial movement of said breech block after said transfer port closure member has moved into said open position.

7. A firearm as claimed in claim 6 in which said transfer control rod engages a second helical compression spring adapted to be compressed during rearward axial movement of said breech block.

8. A firearm as claimed in claim 7 in which said second helical compression spring is disposed within the stock of the firearm.

9. A firearm as claimed in claim 6 in which said transfer control rod is adapted on rearward movement thereof to cock said trigger operated means.

10. A firearm as claimed in claim 9 in which said barrel and said magazine tube are disposed generally side by side and in which said transfer control rod is disposed below said barrel.

References Cited UNITED STATES PATENTS 3/1891 Maxim 4217 1/1907 Dehm 42l7 US. Cl. X.R. 4249 

